70 lines
		
	
	
		
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			70 lines
		
	
	
		
			2.7 KiB
		
	
	
	
		
			Plaintext
		
	
	
	
	
	
| Advent of Code
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| 
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| --- Day 24: Air Duct Spelunking ---
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| 
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|    You've finally met your match; the doors that provide access to the roof are locked tight, and all of the controls and
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|    related electronics are inaccessible. You simply can't reach them.
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| 
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|    The robot that cleans the air ducts, however, can.
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| 
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|    It's not a very fast little robot, but you reconfigure it to be able to interface with some of the exposed wires that
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|    have been routed through the HVAC system. If you can direct it to each of those locations, you should be able to bypass
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|    the security controls.
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| 
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|    You extract the duct layout for this area from some blueprints you acquired and create a map with the relevant locations
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|    marked (your puzzle input). 0 is your current location, from which the cleaning robot embarks; the other numbers are (in
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|    no particular order) the locations the robot needs to visit at least once each. Walls are marked as #, and open passages
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|    are marked as .. Numbers behave like open passages.
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| 
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|    For example, suppose you have a map like the following:
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| 
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|  ###########
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|  #0.1.....2#
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|  #.#######.#
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|  #4.......3#
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|  ###########
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| 
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|    To reach all of the points of interest as quickly as possible, you would have the robot take the following path:
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| 
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|      • 0 to 4 (2 steps)
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|      • 4 to 1 (4 steps; it can't move diagonally)
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|      • 1 to 2 (6 steps)
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|      • 2 to 3 (2 steps)
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| 
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|    Since the robot isn't very fast, you need to find it the shortest route. This path is the fewest steps (in the above
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|    example, a total of 14) required to start at 0 and then visit every other location at least once.
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| 
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|    Given your actual map, and starting from location 0, what is the fewest number of steps required to visit every non-0
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|    number marked on the map at least once?
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| 
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|    Your puzzle answer was ____.
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| 
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| --- Part Two ---
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| 
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|    Of course, if you leave the cleaning robot somewhere weird, someone is bound to notice.
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| 
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|    What is the fewest number of steps required to start at 0, visit every non-0 number marked on the map at least once, and
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|    then return to 0?
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| 
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|    Your puzzle answer was _____.
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| 
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| 
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| References
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| 
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|    Visible links
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|    . http://adventofcode.com/
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|    . http://adventofcode.com/2016/about
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|    . http://adventofcode.com/2016/support
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|    . http://adventofcode.com/2016/events
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|    . http://adventofcode.com/2016/settings
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|    . http://adventofcode.com/2016/auth/logout
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|    . http://adventofcode.com/2016
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|    . http://adventofcode.com/2016
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|    . http://adventofcode.com/2016/leaderboard
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|    . http://adventofcode.com/2016/stats
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|    . http://adventofcode.com/2016/sponsors
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|    . http://adventofcode.com/2016/sponsors
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|    . https://en.wikipedia.org/wiki/HVAC
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|    . http://adventofcode.com/2016
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|    . http://adventofcode.com/2016/day/24/input
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